and formation of cavities (more than 2 cm)[1] containing necrotic debris
or fluid caused by microbial infection.This pus-filled cavity is often caused by aspiration, which may occur during altered consciousness. Alcoholism is the most common condition predisposing to lung abscesses.
Lung abscess is considered primary (60%[2]) when it results from existing lung parenchymal process and is termed secondary when it complicates another process e.g. vascular emboli or follows rupture of extrapulmonaryextrapulmonaryabscess into lung.